/*
 * To change this template, choose Tools | Templates
 * and open the template in the editor.
 */
package servlet;

import com.google.inject.Inject;
import com.google.inject.Singleton;
import exception.MachineInfoNotCompleteException;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.Iterator;
import java.util.List;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import exception.BuildNameNotSetException;
import model.Machine;
import model.RealMachine;
import model.VMMachine;
import model.MachineManager;

/**
 *
 * @author pyin
 */
@Singleton
public class VMStateServlet extends HttpServlet {

    private MachineManager machineFactory;

    @Inject
    public VMStateServlet(MachineManager factory){
        this.machineFactory = factory;
    }

    /** 
     * Processes requests for both HTTP <code>GET</code> and <code>POST</code> methods.
     * @param request servlet request
     * @param response servlet response
     * @throws ServletException if a servlet-specific error occurs
     * @throws IOException if an I/O error occurs
     */
    protected void processRequest(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        response.setContentType("text/html;charset=UTF-8");
        PrintWriter out = response.getWriter();
        try {
            /* TODO output your page here
            out.println("<html>");
            out.println("<head>");
            out.println("<title>Servlet VMStateServlet</title>");  
            out.println("</head>");
            out.println("<body>");
            out.println("<h1>Servlet VMStateServlet at " + request.getContextPath () + "</h1>");
            out.println("</body>");
            out.println("</html>");
             */
        } finally {
            out.close();
        }
    }

    // <editor-fold defaultstate="collapsed" desc="HttpServlet methods. Click on the + sign on the left to edit the code.">
    /** 
     * Handles the HTTP <code>GET</code> method.
     * @param request servlet request
     * @param response servlet response
     * @throws ServletException if a servlet-specific error occurs
     * @throws IOException if an I/O error occurs
     */
    @Override
    protected void doGet(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
 
            List machines = this.machineFactory.getVMMachines();
            Iterator it = machines.iterator();
            while (it.hasNext()) {
                Machine machine = (Machine) it.next();
                if (machine instanceof VMMachine) {
                    renderVMMachine((VMMachine) machine, response);
                } else {
                    renderRealMachine((RealMachine) machine, response);
                }
            }

    }

    private void renderRealMachine(RealMachine machine, HttpServletResponse response){
        if(machine.isStarted())
            try {
            response.getWriter().println("<div class='success'>" + machine.getName() + " is OK.</div>");
        } catch (IOException ex) {
            Logger.getLogger(VMStateServlet.class.getName()).log(Level.SEVERE, null, ex);
        }

    }

    private void renderVMMachine(VMMachine machine, HttpServletResponse response) {
        try {
            boolean hostingMachineRunning;
            boolean vmReady;
            boolean isMachineRunning;
            hostingMachineRunning = machine.isHostingMachineReady();
            if (hostingMachineRunning) {
                isMachineRunning = machine.isStarted();
                if (isMachineRunning) {
                    vmReady = machine.hasCurrentBuildSnapshot();
                    if (hostingMachineRunning && vmReady) {
                        response.getWriter().print("<div class='success'>"+machine.getName() + " is OK.</div>");
                    }
                    if (!hostingMachineRunning) {
                        response.getWriter().print("hosting machine for " + machine.getName() + " is down");
                    }
                    if (hostingMachineRunning && !vmReady) {
                        response.getWriter().print(machine.getName() + " is not setup");
                    }
                }
            }
        } catch (BuildNameNotSetException e) {
            try {
                response.getWriter().print(e.getMessage() + "<br>");
            } catch (IOException ex) {
                Logger.getLogger(VMStateServlet.class.getName()).log(Level.SEVERE, null, ex);
            }
        }
        catch (IOException e) {
        }
    }

    /** 
     * Handles the HTTP <code>POST</code> method.
     * @param request servlet request
     * @param response servlet response
     * @throws ServletException if a servlet-specific error occurs
     * @throws IOException if an I/O error occurs
     */
    @Override
    protected void doPost(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        processRequest(request, response);
    }

    /** 
     * Returns a short description of the servlet.
     * @return a String containing servlet description
     */
    @Override
    public String getServletInfo() {
        return "Short description";
    }// </editor-fold>
}
